1. Field of the Invention
The present invention relates to a wireless communication system and, more particularly, to a wireless communication system and a channel changing method capable of changing an available channel to a channel having no cross talk when there occurs channel cross talk in a wireless communication system.
2. Description of Related Art
Recently, personal computers are widely being used, so almost everyone uses the computer. Such a computer has a human interface device (HID) connected thereto, and receives data transmitted from the HID and performs an operation corresponding to the data.
The human interface device generally refers to all devices which are used to process an interface between a human and a computer or peripheral equipment, which includes a keyboard, a mouse, a wireless sensor, a mobile phone, a notebook, a digital camera, and the like.
Such a human interface device gradually employs wireless communication technology in order to maximize user convenience.
The main system such as a computer further includes a separate device (a base terminal) performing wireless communication with the human input device so that it performs not only the wireless communication with the human input device but also various kinds of tasks using data provided from the human interface device.
Hereinafter, for the convenience of description, the human interface device performing the wireless communication with the base terminal is referred to as a wireless input device, and a wireless optical mouse is employed as an example of the wireless input device.
FIG. 1 is an internal block diagram of a wireless communication system. Referring to FIG. 1, the wireless communication system includes: a wireless input device 10 for setting a channel used to perform wireless communication with a base terminal 20 and performing the wireless communication on the channel; the base terminal 20 for assigning a channel corresponding to the wireless input device 10 and performing the wireless communication with the wireless input device 10 on the channel, and providing data of the wireless input device 10 obtained from the wireless communication to a main system 30; and the main system 30 for performing a variety of tasks in response to the data provided from the base terminal 20.
The wireless data generated from the wireless input device 10 for the wireless communication includes a unique ID of the wireless input device 10 and an error check code such that the base terminal 20 can identify the wireless input device 10 that has transmitted the wireless data. Further, the base terminal 20 can recognize whether or not the received wireless data is erroneous using the unique ID and the error check code.
However, the conventional base terminal 20 and wireless input device 10 employ an one-way communication scheme, wherein the base terminal 20 analyzes the wireless data received from the wireless input device 10 and determines whether or not the data was erroneous using the unique ID and the error check code.
At this time, most of cases where the wireless data received from the wireless input device 10 is erroneous are due to cross talk in current using channel. Further, although the error generated due to the channel cross talk in the base terminal 20 was sensed, there was no way how to inform the wireless input device 10 of the error occurrence.
Accordingly, when the user senses the error generated due to the channel cross talk, there is an inconvenience that he or she has to set manually a new channel between the wireless input device 10 and the base terminal 20 in manual. Further, there is a problem that efficiency and reliability of the wireless communication abruptly reduce since it is not possible to overcome the error generation promptly.
When setting the available channel again, the wireless input device 10 should scan a plurality of whole channels and should obtain an available channel out of the scanned channels since there is no information on the available channel. So, there were drawbacks that considerable time is unnecessarily wasted and accordingly it takes much time to change the channel.
Further, in the conventional wireless input device 10, its own channel cannot be prevented from another wireless device using the same channel band as the channel currently assigned to the wireless input device, so that the wireless input device 10 may be deprived of the channel when it does not use the channel for a predetermined time such as a power saving mode.
Furthermore, the conventional base terminal 20 has a problem in that it takes a long time to sense the channel cross talk since it depends on only the unique ID and the error detection code to determine whether or not the channel cross talk occurs.